A new topometric method of determining the position of the venous angle on cerebral phlebograms

The authors devised their own craniometric method of determining the normal position of the venous angle on the lateral phlebogram. The fundamental principles of the method are as follows: (1) two auxiliary lines; i.e. (a) a horizontal line the nasion - the tuberculum sellae (N-TS); (b)a diagonal line the nasion - the tabula interna (N-Ti); (2) the two auxiliary lines form the angle alpha, which is equal to 20.44+/- 4.2 degree; (3) the proportional position of the venous angle (the point of intersection S on the diagonal N-Ti) is the ratio of the distance N-S to the total length of the diagonal N-Ti,i.e.: (formula: see text). The value is equal to 49.8 +/- 4.6%. The present method takes into consideration both the length and the height of the skull, has a small statistical dispersion and is simpler than the other available methods.